Although the imaging technology based on color channels meets the imaging requirements of the human vision system, spectrum information of the scene is lost during the integrating process of the scene light spectrum in the camera sensors. The lost information is the key property for reflecting the physical characteristics of the light source and the scene, and thus it is important to solve the problem of sampling the spectrum information of the scene. Starting from this, many researches on sampling the spectrum information have been performed.
The spectrum technology and the optical imaging technology are two widely used technologies. The spectrum technology mainly adopts the physical characteristics of the light (such as the dispersion and the diffraction) and the band-pass characteristics of the filter for the spectrum domain to transform a single beam of light into a plurality of light, each of which has a single spectrum. After the light is separated in the spectrum dimension, the light intensities in different spectral bands can be detected independently by the light sensor, such that the spectrum information of the detected light can be sampled. On the other hand, with the rapid development of the sensor technology, the imaging technology based on the CCD (Charge Coupled Device) electric coupler becomes mature gradually. The CCD electric coupler can directly capture the light and transform the optical signal to the analog current signal, and the image can be obtained conveniently after amplifying and analog-to-digital converting the analog current signal. Recently, researchers combine the imaging technology with the spectrum technology to sample the scene both in the spatial dimension and in the spectral dimension, thus prompting the development of the hyper spectral sampling based on the imaging technology.
The color (red, green and blue) channel intensities of each pixel in the conventional image are replaced with a vector having intensity information of the light at different wavelengths, and thus the hyper spectrum image of the scene with a high resolution is a data block. In addition of the two spatial dimensions x and y, a spectrum dimension A is added into the spectrum data of the scene. With reference to the fact that the spectral resolution of the scene is determined by the number and continuity of the spectrum channels, the related sampling methods are classified into the multi-spectrum sampling and the hyper spectrum sampling (generally, the multi-spectrum sampling covers the infrared region and has a small number of narrow spectrum channels, however, the hyper spectrum sampling refers to the continuous and multichannel sampling in the visible range). Recently, the hyper spectrum imaging of the scene at a single time cannot meet the requirements of the research and application, and thus the hyper spectrum video sampling technology with a high resolution has been developed continuously. The sampled data expended from the spatial dimension to the spectrum dimension, and further to the time dimension. In other words, in addition of the spatial dimensions x, y and the spectrum dimension λ, a time dimension t is added into the spectrum data. Thus, the spectrum data of the dynamic scene can be captured and recorded in real time.
Due to a high dimension of the hyper spectrum video with the high resolution itself, it is hard to directly capture the hyper spectrum video with the high resolution. Thus, there is a need to propose a method for sampling the spectrum video information with the high resolution.